A brief discussion on the welding processes and characteristics of wire harness welding

Thread Content

Wiring harness welding is commonly used in automobile manufacturing. If you are also interested in learning about the principles and advantages of wiring harness welding, you can visit Binenxin. Binenxin not only provides information related to wiring harness welding but also offers sales of wiring harness welding machines. Harness welding is a welding technique that was developed to solve problems related to welding in automobiles. Next, I will briefly introduce harness welding. Everyone can gain a preliminary understanding of wire harness welding through the following content. More knowledge about wire harness welding can be found online. Traditional wiring harness welding: The main traditional wiring harness welding processes include fusion welding, fiber welding, and pressure welding. 1) Fusion welding is a welding method in which the joint between the workpieces is heated to a molten state, and welding is carried out without applying pressure. During fusion welding, the heat source rapidly heats and melts the joint between the two workpieces to be welded, forming a molten pool. The molten pool moves forward with the heat source; upon cooling, it forms a continuous weld that joins the two workpieces together. After fusion welding, the wiring harness joints are bonded together in a welded lump formation, resulting in high resistance, which **reduces the service life of the wiring harness. Moreover, during the fusion welding process, if the atmosphere comes into direct contact with the high-temperature molten pool, the oxygen in the atmosphere will oxidize the metal and various alloying elements. Nitrogen, water vapor, and other substances present in the atmosphere that enter the molten pool can also cause defects such as pores, inclusions, and cracks in the weld during the subsequent cooling process, thereby deteriorating the quality and performance of the weld. 2) Brazing is a welding method that uses a metal material with a melting point lower than that of the workpiece as a filler metal. The workpiece and the filler metal are heated to a temperature higher than the melting point of the filler metal but lower than that of the workpiece; the liquid filler metal then wets the workpiece, fills the gaps at the joint, and enables atomic diffusion between the workpiece and the filler metal, thereby achieving welding. The joint formed between two joined objects during welding is called a weld. The areas on either side of the weld are affected by the welding heat during welding, resulting in changes in their structure and properties; this region is known as the heat-affected zone. During welding, due to differences in the workpiece material, welding material, welding current, etc., overheating, embrittlement, hardening, or softening may occur in the weld and heat-affected zone after welding. This also reduces the properties of the welded part and deteriorates its weldability. This requires adjusting the welding conditions; preheating the joint of the workpieces before welding, maintaining heat during welding, and performing post-weld heat treatment can improve the welding quality of the workpieces. 3) Pressure welding is a process in which two workpieces are brought together under pressure to achieve atomic bonding in the solid state; it is also known as solid-state welding. The commonly used pressure welding process is resistance spot welding; when current flows through the joint between the two workpieces, the temperature rises due to the high resistance at that location. Once the material reaches a plastic state, it is joined together under axial pressure. The common feature of various pressure welding methods is that pressure is applied during the welding process without the use of filler material. Most pressure welding methods, such as diffusion welding, high-frequency welding, and cold pressure welding, do not involve a melting process; as a result, there is no loss of beneficial alloying elements or intrusion of harmful elements into the weld, just as in fusion welding. This simplifies the welding process and improves the safety and hygiene conditions associated with welding. At the same time, since the heating temperature is lower than that in fusion welding and the heating time is shorter, the heat-affected zone is small. Many materials that are difficult to weld using fusion welding can often be joined by pressure welding to produce joints with strength equal to that of the base material. Advantages of wire harness welding machines in welding: (1) The welding material does not melt, retaining its metallic properties. (2) It has good electrical conductivity after welding, with an extremely low resistance coefficient or one that is practically zero. (3) It has low requirements for the surface of the welded metal; it can be welded either oxidized or electroplated. (4) Short welding time, with no need for any flux, gas, or solder. (5) Welding produces no sparks, ensuring environmental protection and safety. Automobile wiring harness welding process 1. Stripping wires: When using wire strippers, care should be taken not to damage the individual wires; multi-strand wires and shielded wires must not be severed, as this will affect the quality of the connection. When stripping multi-strand wires, make sure to twist the core wires into a spiral shape. The wire stripping length is determined in accordance with the requirements specified in the process documentation. 2. Pre-soldering: Pre-soldering is a crucial step in wire welding. When applying solder to the wires, they should be rotated while being coated with solder, with the direction of rotation matching the direction of twisting. When soldering multiple wires together, care must be taken to avoid the “wax wick effect,” whereby the solder penetrates into the insulating layer, causing the wire to become hard and leading to connection failures. 3. Heating: First, use the preheated soldering iron tip to heat the component leads and pads. 4. Wire feeding: Hold the solder wire with both hands and feed it to the heated area to be welded. 5. Remove: Once the solder wire has melted and is flowing slowly over two-thirds of the surface of the pad, quickly withdraw the solder wire and the soldering iron tip. 6. Solidification: After withdrawing the Soldering iron, avoid disturbing the components and circuit board; let the solder joints solidify naturally. For components that are prone to damage, blowing air on the welds can help accelerate solidification. 7. Inspection: Check the welding quality; the amount of solder in the solder joints should be appropriate, the joints should be shiny, and the welding should be secure. Harness welding mainly involves welding harnesses; it is widely used in the electronics industry, as this industry makes extensive use of harnesses. Everyone can learn some knowledge related to wire harness welding, or study various methods of wire harness welding; this is very helpful for improving one’s skills. Welding wire harnesses is quite challenging, so one must study it carefully.